A blood transfusion is a fairly simple medical procedure during which a patient receives whole blood or one of its parts through an intravenous line, or IV. This is a tiny tube that is inserted into a vein using a small needle.

While patients are likely to notice a brief pinch of the needle, a blood transfusion is considered to be relatively painless. Still, any procedure that involves a needle is likely to cause some anxiety for a child, so it helps to understand how a transfusion is done. That way you can feel confident about what is happening and help put your child at ease.

About Blood Transfusions

Blood is like the body's transportation system. As blood circulates, it delivers oxygen and nutrients throughout the body. It also collects waste products and carries them to the organs responsible for making sure the wastes leave the body.

Whole blood is a mixture of cells and liquid, and each part has a specific job:

White blood cells help defend the body against infection. They do this by producing antibodies, which help destroy foreign germs in the body.

Platelets, the smallest blood cells, help to clot the blood and control bleeding.

Plasma is the liquid part of whole blood and contains a mixture of water, proteins, electrolytes, carbohydrates, cholesterol, hormones, and vitamins.

A blood transfusion can make up for a loss of blood or any part of the blood. Although whole blood can be transfused, it is rarely used. Instead, more specific parts of blood are transfused as needed. Red blood cells are the most commonly transfused part, to increase the blood's ability to carry oxygen and prevent fatigue and other complications.

Transfusions take 1 to 4 hours, depending on how much blood and what type is given, and no special recovery time is needed.

Most transfusions are done in a hospital, but they can be done elsewhere when necessary. In most cases, the blood comes from volunteer donors. The blood of the donor, which is carefully screened to ensure its safety, must match the blood of the person receiving it.

Why Blood Transfusions Are Performed

The three main reasons why a child may need a blood transfusion are:

Loss of blood. A child may need a transfusion because of blood loss during surgery or from an injury or an illness.

An inability to make enough blood. Blood cells are made in the bone marrow, a spongy substance within the bones in the body. Some illnesses and treatments can interfere with the marrow's ability to make blood. For example, people with cancer often need blood transfusions because chemotherapy decreases the bone marrow's production of new blood cells.

To prevent complications from an existing blood disorder. Children with sickle cell disease, thalassemia, or anemia caused by kidney disease may benefit from regular transfusions to boost their blood's ability to carry oxygen. And those who have bleeding disorders, such as hemophilia or von Willebrand disease, may need to be transfused with a specific type of plasma to help prevent serious bleeding.

Where the Blood Comes From

Since there's no manmade substitute for blood, the blood supply used for transfusion must be donated. The three types of blood donation are:

Autologous blood donation. Sometimes, when people know in advance that they are going to need a transfusion (for a planned surgery, for example), they may donate their own blood beforehand. In general, kids don't donate their own blood until they are over age 12.

Directed donation. This is when a family member or friend with a compatible blood type donates blood specifically to be used by a designated patient.

Volunteer donation. Since there's no medical evidence that blood from directed donors is any safer than blood from volunteer donors, most patients receive blood donated through blood drives, which are often run by independent collection agencies like the American Red Cross.

Some people worry about getting diseases from infected blood, but the United States has one of the safest blood supplies in the world. Many organizations, including community blood banks and the federal government, work hard to ensure that the blood supply is safe.

The risk of contracting a disease like HIV or hepatitis is extremely low in the United States today because of very strict blood screening. Also, the needles and other equipment used are sterile and they're used only on one person and then thrown away.

Preparing for a Blood Transfusion

Once it's determined that your child needs a blood transfusion, the doctor will speak with you about the procedure. Even if the doctor already has your child's medical history, he or she may review parts of it with you, double-checking items like allergies. The doctor will also ask if your child has ever received blood in the past, and if so, if there were any reactions.

You'll also have the opportunity to ask questions about the procedure. When you feel comfortable with the information and your questions have been fully answered, you'll be asked to sign an informed consent form, stating that you understand the procedure and its risks, and give your permission for your child to have the blood transfusion.

If the situation is not a life-threatening emergency, two tests will be performed:

Blood typing. To confirm your child's blood type, a nurse or technician will draw a sample from a vein in your child's arm using a sterile needle. (Except for the brief needle stick, this isn't painful and only takes a few minutes.) This blood is immediately labeled with your child's name, birth date, and medical record number, and an armband with matching information is made for your child to wear. The blood is then sent to the hospital's blood bank lab, where technicians test it for blood type.

Cross-matching. Once typing is complete, a compatible donor blood is chosen. As a final check, a blood bank technologist will mix a small sample of your child's blood with a small sample of the donor blood to confirm they are compatible. If they clump together, the blood is not compatible. If the blood mixes smoothly, they are. Blood that is considered compatible is then labeled with your child's name, birth date, and medical record number and delivered to where your child will be receiving the transfusion.

During the Procedure

A transfusion can take place anywhere it is necessary. Most transfusions occur in a hospital setting, often at a patient's bedside, in the operating room, in the emergency room, or in the chemotherapy unit. They can also be performed in an outpatient care clinic or even at home, if necessary.

As long as the transfusion is not being done during surgery, you'll be able to stay with your child, who will be awake. Your child can sit comfortably in a reclining chair or lie down on a bed, watch a movie, listen to music, or play quietly, and may also be able to eat and drink, walk around a bit, and use the bathroom.

Starting an IV Line

A nurse will begin an intravenous line (IV). After the needle is inserted into an arm or hand, a tiny plastic tube is left in the vein and attaches to the IV tubing, which is then used to connect to the bag containing the blood.

Since puncturing the skin involves a small needle, starting an IV can cause a little bit of pain (kind of like a small pinch). To reduce discomfort, a nurse might put some numbing cream on your child's skin a half hour before inserting the needle.

Though the vein is typically in the arm or hand, it can be done in many other places, if necessary, especially if conditions like severe dehydration or blood loss have made the veins harder to find. For example, babies often receive transfusions through veins in their foot or scalp.

Children who need many transfusions may require a central line (a tube inserted into a larger vein in the chest) or a PICC line (a longer tube inserted through a vein near the bend of the elbow). These lines allow easy access, and they also spare the smaller veins the damage that can come from repeated punctures.

Giving Medications

Most kids don't require any special medications before or during a blood transfusion. However, if your child has had a mild reaction during a transfusion before — the doctor may give your child some medication just before the procedure. These may be given by mouth or through the IV.

Cross-Checking the Blood

Just before the transfusion, two nurses will read to each other the names and identification numbers on your child's armband and on the blood that came from the blood bank. The transfusion won't begin unless there is a match.

Transfusing the Blood

The blood bag is hung upside down from an IV pump that controls the speed of the flow. The blood flows out of the bag, into the tubing, through the tiny tube in the skin, and into the bloodstream. The whole process takes about 1 to 4 hours, depending on how much blood is given.

The nurse will take your child's blood pressure, body temperature, and pulse several times throughout the procedure. Your child will also be watched closely for any signs of an allergic or other type of reaction, including rash, fever, headache, or swelling.

After the Procedure

After a transfusion, the tiny plastic tube is removed from the vein and a bandage is placed over the area. The site may be slightly sore or tingly for a little while. Medication may be given for any mild side effects, such as fever or headache.

If the transfusion was not done as part of a surgery or because of an injury or illness causing blood loss, there is no special recovery time needed and your child may leave the hospital shortly after the procedure.

Benefits

In children with anemia or those undergoing chemotherapy, the biggest benefits of transfusions are increased blood flow to nourish the organs and improved oxygen levels in the body. This can keep them from feeling extreme fatigue and help give them enough energy for the activities of daily life. Benefits like this are often felt fairly quickly.

For patients with bleeding problems, transfusions with platelets or plasma can help to control or prevent bleeding complications.

Risks and Complications

Serious reactions to transfusions are rare, but, as for any medical procedure, there are a few potential risks. These may include:

Fever. Patients may get a fever, sometimes along with chills, a headache, or nausea. These can be caused by a reaction between the recipient's immune system and specific types of proteins in the donor blood. When this happens, doctors will stop the transfusion to make sure there is not a serious problem and give the patient fever-reducing medication. In most cases the transfusion is restarted soon after.

Allergic reaction. Allergic reactions (like hives or itching) occur when the recipient's immune system reacts with proteins in the donor blood. In rare cases, an allergic reaction can be severe (a condition called anaphylaxis). Stopping the transfusion and giving the patient medications such as antihistamines and steroids can treat a reaction. If the reaction is mild and responds to medication, the transfusion can start again. If it is more serious, the focus will be on treating the reaction.

Hemolytic reaction. If a patient's blood type and the donor blood type do not match, the result can be a life-threatening condition called a hemolytic reaction. This means the recipient's immune system attacks the red blood cells in the donated blood and destroys them. If a hemolytic reaction appears to be occurring, doctors stop the transfusion right away and treat the symptoms. Reactions like this are very rare because health care professionals take many precautions to confirm that the patient's and donor's blood type are compatible before giving a transfusion.

Alternatives

During surgery, doctors try to reduce the need for transfusions by minimizing blood loss. In some cases, they may even be able to collect blood lost during surgery and return it to the patient. But until science develops a manmade blood source, there is no acceptable alternative to a blood transfusion in many situations.

Certain medications called growth factors are sometimes used to increase the body's ability to make blood. These include erythropoietin and thrombopoetin, which stimulate red blood cell and platelet production. In some patients, particularly newborns with anemia or a child experiencing anemia due to kidney disease, medications like these may have some benefits. But in most cases they don't entirely replace the need for a transfusion.

When your child is having any kind of procedure, it's understandable to be a little uneasy. But it helps to know that in most cases, blood transfusions are common procedures and complications are rare. If you have any questions about transfusions, talk with your doctor.